diff options
Diffstat (limited to 'drivers/iio/magnetometer/af8133j.c')
| -rw-r--r-- | drivers/iio/magnetometer/af8133j.c | 528 |
1 files changed, 528 insertions, 0 deletions
diff --git a/drivers/iio/magnetometer/af8133j.c b/drivers/iio/magnetometer/af8133j.c new file mode 100644 index 000000000000..742bbdf25f08 --- /dev/null +++ b/drivers/iio/magnetometer/af8133j.c @@ -0,0 +1,528 @@ +// SPDX-License-Identifier: GPL-2.0-only +/* + * af8133j.c - Voltafield AF8133J magnetometer driver + * + * Copyright 2021 Icenowy Zheng <icenowy@aosc.io> + * Copyright 2024 Ondřej Jirman <megi@xff.cz> + */ + +#include <linux/delay.h> +#include <linux/gpio/consumer.h> +#include <linux/i2c.h> +#include <linux/module.h> +#include <linux/pm_runtime.h> +#include <linux/regmap.h> +#include <linux/regulator/consumer.h> + +#include <linux/iio/iio.h> +#include <linux/iio/trigger_consumer.h> +#include <linux/iio/triggered_buffer.h> + +#define AF8133J_REG_OUT 0x03 +#define AF8133J_REG_PCODE 0x00 +#define AF8133J_REG_PCODE_VAL 0x5e +#define AF8133J_REG_STATUS 0x02 +#define AF8133J_REG_STATUS_ACQ BIT(0) +#define AF8133J_REG_STATE 0x0a +#define AF8133J_REG_STATE_STBY 0x00 +#define AF8133J_REG_STATE_WORK 0x01 +#define AF8133J_REG_RANGE 0x0b +#define AF8133J_REG_RANGE_22G 0x12 +#define AF8133J_REG_RANGE_12G 0x34 +#define AF8133J_REG_SWR 0x11 +#define AF8133J_REG_SWR_PERFORM 0x81 + +static const char * const af8133j_supply_names[] = { + "avdd", + "dvdd", +}; + +struct af8133j_data { + struct i2c_client *client; + struct regmap *regmap; + /* + * Protect device internal state between starting a measurement + * and reading the result. + */ + struct mutex mutex; + struct iio_mount_matrix orientation; + + struct gpio_desc *reset_gpiod; + struct regulator_bulk_data supplies[ARRAY_SIZE(af8133j_supply_names)]; + + u8 range; +}; + +enum af8133j_axis { + AXIS_X = 0, + AXIS_Y, + AXIS_Z, +}; + +static struct iio_mount_matrix * +af8133j_get_mount_matrix(struct iio_dev *indio_dev, + const struct iio_chan_spec *chan) +{ + struct af8133j_data *data = iio_priv(indio_dev); + + return &data->orientation; +} + +static const struct iio_chan_spec_ext_info af8133j_ext_info[] = { + IIO_MOUNT_MATRIX(IIO_SHARED_BY_DIR, af8133j_get_mount_matrix), + { } +}; + +#define AF8133J_CHANNEL(_si, _axis) { \ + .type = IIO_MAGN, \ + .modified = 1, \ + .channel2 = IIO_MOD_ ## _axis, \ + .address = AXIS_ ## _axis, \ + .info_mask_separate = BIT(IIO_CHAN_INFO_RAW), \ + .info_mask_shared_by_type = BIT(IIO_CHAN_INFO_SCALE), \ + .info_mask_shared_by_type_available = BIT(IIO_CHAN_INFO_SCALE), \ + .ext_info = af8133j_ext_info, \ + .scan_index = _si, \ + .scan_type = { \ + .sign = 's', \ + .realbits = 16, \ + .storagebits = 16, \ + .endianness = IIO_LE, \ + }, \ +} + +static const struct iio_chan_spec af8133j_channels[] = { + AF8133J_CHANNEL(0, X), + AF8133J_CHANNEL(1, Y), + AF8133J_CHANNEL(2, Z), + IIO_CHAN_SOFT_TIMESTAMP(3), +}; + +static int af8133j_product_check(struct af8133j_data *data) +{ + struct device *dev = &data->client->dev; + unsigned int val; + int ret; + + ret = regmap_read(data->regmap, AF8133J_REG_PCODE, &val); + if (ret) { + dev_err(dev, "Error reading product code (%d)\n", ret); + return ret; + } + + if (val != AF8133J_REG_PCODE_VAL) { + dev_warn(dev, "Invalid product code (0x%02x)\n", val); + return 0; /* Allow unknown ID so fallback compatibles work */ + } + + return 0; +} + +static int af8133j_reset(struct af8133j_data *data) +{ + struct device *dev = &data->client->dev; + int ret; + + if (data->reset_gpiod) { + /* If we have GPIO reset line, use it */ + gpiod_set_value_cansleep(data->reset_gpiod, 1); + udelay(10); + gpiod_set_value_cansleep(data->reset_gpiod, 0); + } else { + /* Otherwise use software reset */ + ret = regmap_write(data->regmap, AF8133J_REG_SWR, + AF8133J_REG_SWR_PERFORM); + if (ret) { + dev_err(dev, "Failed to reset the chip\n"); + return ret; + } + } + + /* Wait for reset to finish */ + usleep_range(1000, 1100); + + /* Restore range setting */ + if (data->range == AF8133J_REG_RANGE_22G) { + ret = regmap_write(data->regmap, AF8133J_REG_RANGE, data->range); + if (ret) + return ret; + } + + return 0; +} + +static void af8133j_power_down(struct af8133j_data *data) +{ + gpiod_set_value_cansleep(data->reset_gpiod, 1); + regulator_bulk_disable(ARRAY_SIZE(data->supplies), data->supplies); +} + +static int af8133j_power_up(struct af8133j_data *data) +{ + struct device *dev = &data->client->dev; + int ret; + + ret = regulator_bulk_enable(ARRAY_SIZE(data->supplies), data->supplies); + if (ret) { + dev_err(dev, "Could not enable regulators\n"); + return ret; + } + + gpiod_set_value_cansleep(data->reset_gpiod, 0); + + /* Wait for power on reset */ + usleep_range(15000, 16000); + + ret = af8133j_reset(data); + if (ret) { + af8133j_power_down(data); + return ret; + } + + return 0; +} + +static int af8133j_take_measurement(struct af8133j_data *data) +{ + unsigned int val; + int ret; + + ret = regmap_write(data->regmap, + AF8133J_REG_STATE, AF8133J_REG_STATE_WORK); + if (ret) + return ret; + + /* The datasheet says "Mesaure Time <1.5ms" */ + ret = regmap_read_poll_timeout(data->regmap, AF8133J_REG_STATUS, val, + val & AF8133J_REG_STATUS_ACQ, + 500, 1500); + if (ret) + return ret; + + ret = regmap_write(data->regmap, + AF8133J_REG_STATE, AF8133J_REG_STATE_STBY); + if (ret) + return ret; + + return 0; +} + +static int af8133j_read_measurement(struct af8133j_data *data, __le16 buf[3]) +{ + struct device *dev = &data->client->dev; + int ret; + + ret = pm_runtime_resume_and_get(dev); + if (ret) { + /* + * Ignore EACCES because that happens when RPM is disabled + * during system sleep, while userspace leave eg. hrtimer + * trigger attached and IIO core keeps trying to do measurements. + */ + if (ret != -EACCES) + dev_err(dev, "Failed to power on (%d)\n", ret); + return ret; + } + + scoped_guard(mutex, &data->mutex) { + ret = af8133j_take_measurement(data); + if (ret) + goto out_rpm_put; + + ret = regmap_bulk_read(data->regmap, AF8133J_REG_OUT, + buf, sizeof(__le16) * 3); + } + +out_rpm_put: + pm_runtime_mark_last_busy(dev); + pm_runtime_put_autosuspend(dev); + + return ret; +} + +static const int af8133j_scales[][2] = { + [0] = { 0, 366210 }, /* 12 gauss */ + [1] = { 0, 671386 }, /* 22 gauss */ +}; + +static int af8133j_read_raw(struct iio_dev *indio_dev, + struct iio_chan_spec const *chan, int *val, + int *val2, long mask) +{ + struct af8133j_data *data = iio_priv(indio_dev); + __le16 buf[3]; + int ret; + + switch (mask) { + case IIO_CHAN_INFO_RAW: + ret = af8133j_read_measurement(data, buf); + if (ret) + return ret; + + *val = sign_extend32(le16_to_cpu(buf[chan->address]), + chan->scan_type.realbits - 1); + return IIO_VAL_INT; + case IIO_CHAN_INFO_SCALE: + *val = 0; + + if (data->range == AF8133J_REG_RANGE_12G) + *val2 = af8133j_scales[0][1]; + else + *val2 = af8133j_scales[1][1]; + + return IIO_VAL_INT_PLUS_NANO; + default: + return -EINVAL; + } +} + +static int af8133j_read_avail(struct iio_dev *indio_dev, + struct iio_chan_spec const *chan, + const int **vals, int *type, int *length, + long mask) +{ + switch (mask) { + case IIO_CHAN_INFO_SCALE: + *vals = (const int *)af8133j_scales; + *length = ARRAY_SIZE(af8133j_scales) * 2; + *type = IIO_VAL_INT_PLUS_NANO; + return IIO_AVAIL_LIST; + default: + return -EINVAL; + } +} + +static int af8133j_set_scale(struct af8133j_data *data, + unsigned int val, unsigned int val2) +{ + struct device *dev = &data->client->dev; + u8 range; + int ret = 0; + + if (af8133j_scales[0][0] == val && af8133j_scales[0][1] == val2) + range = AF8133J_REG_RANGE_12G; + else if (af8133j_scales[1][0] == val && af8133j_scales[1][1] == val2) + range = AF8133J_REG_RANGE_22G; + else + return -EINVAL; + + pm_runtime_disable(dev); + + /* + * When suspended, just store the new range to data->range to be + * applied later during power up. + */ + if (!pm_runtime_status_suspended(dev)) + scoped_guard(mutex, &data->mutex) + ret = regmap_write(data->regmap, + AF8133J_REG_RANGE, range); + + pm_runtime_enable(dev); + + data->range = range; + return ret; +} + +static int af8133j_write_raw(struct iio_dev *indio_dev, + struct iio_chan_spec const *chan, + int val, int val2, long mask) +{ + struct af8133j_data *data = iio_priv(indio_dev); + + switch (mask) { + case IIO_CHAN_INFO_SCALE: + return af8133j_set_scale(data, val, val2); + default: + return -EINVAL; + } +} + +static int af8133j_write_raw_get_fmt(struct iio_dev *indio_dev, + struct iio_chan_spec const *chan, + long mask) +{ + return IIO_VAL_INT_PLUS_NANO; +} + +static const struct iio_info af8133j_info = { + .read_raw = af8133j_read_raw, + .read_avail = af8133j_read_avail, + .write_raw = af8133j_write_raw, + .write_raw_get_fmt = af8133j_write_raw_get_fmt, +}; + +static irqreturn_t af8133j_trigger_handler(int irq, void *p) +{ + struct iio_poll_func *pf = p; + struct iio_dev *indio_dev = pf->indio_dev; + struct af8133j_data *data = iio_priv(indio_dev); + s64 timestamp = iio_get_time_ns(indio_dev); + struct { + __le16 values[3]; + s64 timestamp __aligned(8); + } sample; + int ret; + + memset(&sample, 0, sizeof(sample)); + + ret = af8133j_read_measurement(data, sample.values); + if (ret) + goto out_done; + + iio_push_to_buffers_with_timestamp(indio_dev, &sample, timestamp); + +out_done: + iio_trigger_notify_done(indio_dev->trig); + + return IRQ_HANDLED; +} + +static const struct regmap_config af8133j_regmap_config = { + .name = "af8133j_regmap", + .reg_bits = 8, + .val_bits = 8, + .max_register = AF8133J_REG_SWR, + .cache_type = REGCACHE_NONE, +}; + +static void af8133j_power_down_action(void *ptr) +{ + struct af8133j_data *data = ptr; + + if (!pm_runtime_status_suspended(&data->client->dev)) + af8133j_power_down(data); +} + +static int af8133j_probe(struct i2c_client *client) +{ + struct device *dev = &client->dev; + struct af8133j_data *data; + struct iio_dev *indio_dev; + struct regmap *regmap; + int ret, i; + + indio_dev = devm_iio_device_alloc(dev, sizeof(*data)); + if (!indio_dev) + return -ENOMEM; + + regmap = devm_regmap_init_i2c(client, &af8133j_regmap_config); + if (IS_ERR(regmap)) + return dev_err_probe(dev, PTR_ERR(regmap), + "regmap initialization failed\n"); + + data = iio_priv(indio_dev); + i2c_set_clientdata(client, indio_dev); + data->client = client; + data->regmap = regmap; + data->range = AF8133J_REG_RANGE_12G; + mutex_init(&data->mutex); + + data->reset_gpiod = devm_gpiod_get_optional(dev, "reset", GPIOD_OUT_HIGH); + if (IS_ERR(data->reset_gpiod)) + return dev_err_probe(dev, PTR_ERR(data->reset_gpiod), + "Failed to get reset gpio\n"); + + for (i = 0; i < ARRAY_SIZE(af8133j_supply_names); i++) + data->supplies[i].supply = af8133j_supply_names[i]; + ret = devm_regulator_bulk_get(dev, ARRAY_SIZE(data->supplies), + data->supplies); + if (ret) + return ret; + + ret = iio_read_mount_matrix(dev, &data->orientation); + if (ret) + return dev_err_probe(dev, ret, "Failed to read mount matrix\n"); + + ret = af8133j_power_up(data); + if (ret) + return ret; + + pm_runtime_set_active(dev); + + ret = devm_add_action_or_reset(dev, af8133j_power_down_action, data); + if (ret) + return ret; + + ret = af8133j_product_check(data); + if (ret) + return ret; + + pm_runtime_get_noresume(dev); + pm_runtime_use_autosuspend(dev); + pm_runtime_set_autosuspend_delay(dev, 500); + ret = devm_pm_runtime_enable(dev); + if (ret) + return ret; + + pm_runtime_put_autosuspend(dev); + + indio_dev->info = &af8133j_info; + indio_dev->name = "af8133j"; + indio_dev->channels = af8133j_channels; + indio_dev->num_channels = ARRAY_SIZE(af8133j_channels); + indio_dev->modes = INDIO_DIRECT_MODE; + + ret = devm_iio_triggered_buffer_setup(dev, indio_dev, NULL, + &af8133j_trigger_handler, NULL); + if (ret) + return dev_err_probe(&client->dev, ret, + "Failed to setup iio triggered buffer\n"); + + ret = devm_iio_device_register(dev, indio_dev); + if (ret) + return dev_err_probe(dev, ret, "Failed to register iio device"); + + return 0; +} + +static int af8133j_runtime_suspend(struct device *dev) +{ + struct iio_dev *indio_dev = dev_get_drvdata(dev); + struct af8133j_data *data = iio_priv(indio_dev); + + af8133j_power_down(data); + + return 0; +} + +static int af8133j_runtime_resume(struct device *dev) +{ + struct iio_dev *indio_dev = dev_get_drvdata(dev); + struct af8133j_data *data = iio_priv(indio_dev); + + return af8133j_power_up(data); +} + +static const struct dev_pm_ops af8133j_pm_ops = { + SYSTEM_SLEEP_PM_OPS(pm_runtime_force_suspend, pm_runtime_force_resume) + RUNTIME_PM_OPS(af8133j_runtime_suspend, af8133j_runtime_resume, NULL) +}; + +static const struct of_device_id af8133j_of_match[] = { + { .compatible = "voltafield,af8133j", }, + { } +}; +MODULE_DEVICE_TABLE(of, af8133j_of_match); + +static const struct i2c_device_id af8133j_id[] = { + { "af8133j", 0 }, + { } +}; +MODULE_DEVICE_TABLE(i2c, af8133j_id); + +static struct i2c_driver af8133j_driver = { + .driver = { + .name = "af8133j", + .of_match_table = af8133j_of_match, + .pm = pm_ptr(&af8133j_pm_ops), + }, + .probe = af8133j_probe, + .id_table = af8133j_id, +}; + +module_i2c_driver(af8133j_driver); + +MODULE_AUTHOR("Icenowy Zheng <icenowy@aosc.io>"); +MODULE_AUTHOR("Ondřej Jirman <megi@xff.cz>"); +MODULE_DESCRIPTION("Voltafield AF8133J magnetic sensor driver"); +MODULE_LICENSE("GPL"); |